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Add camel-aws2-s3-starter. AWS credentials are resolved automatically using the default credential chain (env vars → system properties → ~/.aws/credentials → IAM role).

<!-- Spring Boot --> <dependency> <groupId>org.apache.camel.springboot</groupId> <artifactId>camel-aws2-s3-starter</artifactId> </dependency> <!-- Standalone Camel --> <dependency> <groupId>org.apache.camel</groupId> <artifactId>camel-aws2-s3</artifactId> </dependency> # application.properties — override default credential chain camel.component.aws2-s3.access-key=${AWS_ACCESS_KEY_ID} camel.component.aws2-s3.secret-key=${AWS_SECRET_ACCESS_KEY} camel.component.aws2-s3.region=us-east-1 On EC2 / ECS / Lambda, leave credentials unconfigured — the component will pick up the IAM role automatically through the instance metadata service. Hardcoding credentials in application.properties is an anti-pattern.

Set the exchange body to the content to upload (byte[], String, InputStream, or File). Set AWS2S3Constants.KEY to the S3 object key and optionally AWS2S3Constants.CONTENT_TYPE for the MIME type.

import org.apache.camel.builder.RouteBuilder; import org.apache.camel.component.aws2.s3.AWS2S3Constants; import org.springframework.stereotype.Component; @Component public class S3UploadRoute extends RouteBuilder { @Override public void configure() { from("direct:upload") // body = file content as byte[] or InputStream .setHeader(AWS2S3Constants.KEY, simple("uploads/${date:now:yyyyMMdd}/${header.filename}")) .setHeader(AWS2S3Constants.CONTENT_TYPE, constant("application/octet-stream")) .to("aws2-s3://my-bucket?operation=putObject") .log("Uploaded to S3: ${header." + AWS2S3Constants.KEY + "}"); } } // Uploading a file from disk from("file:/tmp/upload?noop=true") .setHeader(AWS2S3Constants.KEY, simple("data/${file:name}")) .to("aws2-s3://my-bucket?operation=putObject");

Set AWS2S3Constants.KEY and use operation=getObject. The response body is an ResponseInputStream — read it or convert it to bytes/String in the next processor.

import org.apache.camel.builder.RouteBuilder; import org.apache.camel.component.aws2.s3.AWS2S3Constants; import org.springframework.stereotype.Component; @Component public class S3DownloadRoute extends RouteBuilder { @Override public void configure() { from("direct:download") .setHeader(AWS2S3Constants.KEY, simple("uploads/${header.filename}")) .to("aws2-s3://my-bucket?operation=getObject") // Convert InputStream → byte[] .convertBodyTo(byte[].class) .log("Downloaded ${header." + AWS2S3Constants.KEY + "}: ${body.length} bytes"); } }

For multi-gigabyte files use streamingUploadMode=true, which internally uses the S3 multipart upload API (5 MB minimum part size). On the download side, keep the body as a stream and pipe it directly to the output — avoid convertBodyTo(byte[].class) which buffers everything in memory.

// Streaming upload — Camel chunks the InputStream automatically from("direct:streamUpload") .setHeader(AWS2S3Constants.KEY, constant("large/big-file.bin")) .setHeader(AWS2S3Constants.CONTENT_TYPE, constant("application/octet-stream")) .to("aws2-s3://my-bucket" + "?operation=putObject" + "&streamingUploadMode=true" + "&streamingUploadPartSize=10485760"); // 10 MB parts // Streaming download — pipe S3 InputStream directly to a file from("direct:streamDownload") .setHeader(AWS2S3Constants.KEY, constant("large/big-file.bin")) .to("aws2-s3://my-bucket?operation=getObject") // Write stream to disk without loading it into memory .to("file:/tmp/downloads?fileName=big-file.bin"); When streaming to file, Camel's File component accepts an InputStream body directly and writes it to disk in chunks. Pair this with streamingUploadMode=true on upload to handle files larger than available heap without OOM errors.

Use from("aws2-s3://...") to poll a bucket. Each new object found becomes a Camel exchange. Combine with moveAfterRead=true to move processed objects to an archive prefix, preventing re-processing.

import org.apache.camel.builder.RouteBuilder; import org.springframework.stereotype.Component; @Component public class S3PollRoute extends RouteBuilder { @Override public void configure() { from("aws2-s3://incoming-bucket" + "?prefix=uploads/" // only watch this prefix + "&delay=60000" // poll every 60 s + "&maxMessagesPerPoll=10" // at most 10 objects per poll + "&moveAfterRead=true" // move to archive prefix after processing + "&destinationBucket=incoming-bucket" + "&destinationBucketPrefix=processed/") .routeId("s3-poller") .log("Processing S3 object: ${header." + AWS2S3Constants.KEY + "}") .convertBodyTo(String.class) .to("direct:handleS3Object"); } }

The S3 component supports a broad set of operations via the operation URI parameter:

OperationDescription
putObjectUpload an object (default for producers).
getObjectDownload an object by key.
deleteObjectDelete a single object by key.
listObjectsList objects in a bucket (returns metadata list).
copyObjectCopy an object between keys or buckets.
createBucketCreate a new S3 bucket.
deleteBucketDelete an empty S3 bucket.
getObjectTagging / setObjectTaggingRead or write S3 object tags.
// Delete an object from("direct:deleteFile") .setHeader(AWS2S3Constants.KEY, simple("uploads/${header.filename}")) .to("aws2-s3://my-bucket?operation=deleteObject"); // List all objects with a given prefix from("direct:listFiles") .setHeader(AWS2S3Constants.PREFIX, constant("reports/")) .to("aws2-s3://my-bucket?operation=listObjects") .log("Objects: ${body}");
OptionDefaultDescription
region—AWS region (e.g. us-east-1). Required.
operationputObjectS3 operation to execute (producer).
prefix—Object key prefix filter (consumer).
delay500Polling interval in milliseconds (consumer).
maxMessagesPerPoll10Max objects fetched per poll cycle (consumer).
moveAfterReadfalseMove object to another prefix/bucket after consuming.
deleteAfterReadtrueDelete the object from S3 after consuming.
streamingUploadModefalseEnable multipart upload for large streaming payloads.
streamingUploadPartSize26214400 (25 MB)Part size in bytes for multipart upload.
useDefaultCredentialsProviderfalseUse AWS default credential chain instead of explicit keys.